Built in the nineteen-twenties by technical engineer Charles Bacchi, the motorcycles were horizontal 125cc and 175cc two-stroke singles.

The engines produced and patented by Bacchi had a split connecting rod and cylinder
could be horizontal or vertical.

The production seems to have been of around one hundred units, but another source says forty motorcycles were built, almost all of 175cc engine capacity.

In 1923 they made two motorcycles in the 350cc class.
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It appears that his brother worked at Frera and Charles Bacchi had access to the facilities of the Tradate factory to bench test and develop his engines. It seems possible that these may have been the inspiration for the 270cc two-stroke engine Frera built in 1923 characterized by a vertical cylinder and external flywheel but there is no documented evidence for this.

In 1927 Charles Bacchi closed the workshops in Milan and joined Moto Guzzi as head of the engine testing division.